The present invention relates to a machine translation system for processing a sentence of a language to translate it into a sentence of another language and, more particularly, to a machine translation system wherein the translated sentence is output together with the original sentence in one-to-one correspondence therewith, thereby simplifying operator inputs for translation processing.
Various types of computer-aided machine translation systems, e.g., a system for translating English sentences to Japanese sentences and vice versa, have been proposed in recent years. Each sentence of input original sentences is divided into words or phrases as processing units for syntactic analysis, and a translation dictionary is accessed for each word or phrase, retrieving a translated word or phrase. Finally, the translated words or phrases are combined into a translated sentence. When two or more translated sentences are obtained for the same original sentence, the original sentence is syntactically analyzed, and any translated sentence regarded as improper in accordance with the analysis results is eliminated.
After the improper translated sentences are eliminated, there still remains a variety of possible translated words or phrases for the translated sentence regarded as proper. More specifically, each original word or phrase often has different parts of speech, different meanings. In order to obtain appropriate equivalents to such an original word or phrase, the translated word or phrase must be selected in accordance with parts of speech and meaning. When a translated word or phrase corresponding to the original word or phrase is changed due to modification, the appropriate translated word or phrase must be selected. In this case, proper selection changes greatly in accordance with the contents of the sentence to be translated, and with the intention of an operator or translator (user), and thus cannot be solely determined. For this reason, the translated sentence is displayed on a display, and the operator selects translation possibilities for each word of the translated sentence, and the operator refers to the corresponding original sentence, thereby properly determining the translated sentence.
In the conventional system, the translated sentence and the original sentence are displayed on a display to allow the operator to compare them. In such a system, the screen is vertically or horizontally divided into halves, with original sentences displayed on one half and translated sentences displayed on the other half. In another conventional system, the original and translated sentences are alternately displayed on a single screen area.
In the system employing the divided screen format, all the original and translated sentences are displayed on corresponding screen areas, exactly in the same form as they have been input and provided. Therefore, it is difficult for the operator to recognize which original sentence corresponds to which translated sentence, making it hard to edit the original or translated sentences efficiently.
When a given translated word is to be corrected, the translator must refer to the corresponding part of the original sentence. In other words, the translator must find that portion of the original sentence which corresponds to the translated word by reading the original text in units of sentences or paragraphs. Therefore, when the corresponding original portion is at the central portion of the original document, or if the original sentence is very long, it will take him or her a long time to find the original portion corresponding to the translated word to be corrected.
In the system employing the latter screen format, the correspondence between the original sentence and the translated sentence is clear. However, the length of the original sentence may differ greatly from that of the translated sentence. This complicates display control. When the original and translated sentences are alternately displayed on the screen, it is inconvenient to read only one of the translated or original sentences at a time.